Drilling a square hole
The funny thing about most (certainly not all) technology is that it has been done before and forgotten. This is readily evident in the medical industry, but here is an example from another field.
May I present: How to drill a square hole, using early 1900’s technology.
upper.us.edu
December 1st, 2006 at 6:44 am
I really do think I should be studying more engineering… that is great
December 1st, 2006 at 9:00 am
It is pretty amazing what people come up with
December 1st, 2006 at 10:42 am
Ah, the old Reuleaux triangle…
I was delighted to see Platypus’ link.
here’s a better square hole drilling explanation.:
tetrahedronhttp://www.integerspin.co.uk/polygon.htm
A couple of months ago, driving, half asleep, to work, I pulled up alongside a shiny new truck, and as we waited for the lights to change, I was admiring all the lightweight aluminium parts, the fuel tanks, tool lockers, wheel rims when…. Suddenly I noticed the wheel nuts were not hex headed as usual. Instead, they were a rather nice radiused triangle- same shape as a Wankel engine’s rotor (http://www.answers.com/topic/wankel-engine). And about ten per wheel. Why?, I wondered. Of course, no normal spanner, socket or wrench would shift them, thus frustrating would be wheel thieves. The driver would have to carry a tool or he’d be stuck if ever he got a flat tyre…
The truck, by the way, was registered in Spain. I’ll be looking out for others, but so far no sightings.
I’ve never seen them anywhere else. I tried the internet and the only reference to nuts of this form was their use on fireplugs in Redwing Minnesota…
Now I’m getting to be a bit of an expert on Reuleaux and his cunning use of eccentrically orbiting wheels.
The british 50 pence and twenty pence coins are Reuleaux polygons, by the way.
http://www.answers.com/topic/wankel-engine,